Note: Results are presented as percentile median ranks of detecting SNP. A
robust measure of variability (Median Absolute Deviation, MAD) is given between
brackets. SNP1 always explains 0.3% of the variance, SNP2 either explains
0.3% (scenario1) or zero% (scenario2). Using GBM, a SNP with a zero main
effect (SNP2, scenario2) is within the19th percentile in 50% of the Monte Carlo
replications. Robust SNP and additive GWAS perform (as expected) only at
chance level (i.e., median percentile rank around 50).